From 10c9ef65fa7d453bfd8b1d82f434f29938d39342 Mon Sep 17 00:00:00 2001
From: drh <>
Date: Fri, 15 Jan 2021 14:25:06 +0000
Subject: [PATCH] Small performance improvement in the EXISTS-to-IN translator
 for the common case where the EXISTS operator is not found in the WHERE
 clause.

FossilOrigin-Name: dcb7772d7695ddbc0fe89e06c07ff4a6ae4fa05de914e2ec10b5cc07a62ed49f
---
 manifest        | 12 ++++++------
 manifest.uuid   |  2 +-
 src/whereexpr.c | 12 ++++++++----
 3 files changed, 15 insertions(+), 11 deletions(-)

diff --git a/manifest b/manifest
index afcc0dca9c..c7f52277ae 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Merge\sthe\slatest\strunk\senhancements\sinto\sthe\sexists-to-in\sbranch.
-D 2021-01-15T14:15:31.281
+C Small\sperformance\simprovement\sin\sthe\sEXISTS-to-IN\stranslator\sfor\sthe\ncommon\scase\swhere\sthe\sEXISTS\soperator\sis\snot\sfound\sin\sthe\sWHERE\sclause.
+D 2021-01-15T14:25:06.079
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -630,7 +630,7 @@ F src/walker.c d9c4e454ebb9499e908aa62d55b8994c375cf5355ac78f60d45af17f7890701c
 F src/where.c 0e6abb22a2323fec80b450825593c26a2ad8f4815d1ee3af9969d8f6144bf681
 F src/whereInt.h 9a3f577619f07700d16d89eeb2f3d94d6b7ed7f109c2dacf0ce8844921549506
 F src/wherecode.c a3a1aff30fe99a818d8e7c607980f033f40c68d890e03ed25838b9dbb7908bee
-F src/whereexpr.c 1f4fac8ea8eac6facb9e80107c659094a56a8ad0b35108717ac99ea57bbc71bc
+F src/whereexpr.c 0ba5c743ee34255658051179441a13297dc2d6b21ef3c41120659ae3dd896ae8
 F src/window.c edd6f5e25a1e8f2b6f5305b7f5f7da7bb35f07f0d432b255b1d4c2fcab4205aa
 F test/8_3_names.test ebbb5cd36741350040fd28b432ceadf495be25b2
 F test/affinity2.test ce1aafc86e110685b324e9a763eab4f2a73f737842ec3b687bd965867de90627
@@ -1896,7 +1896,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 897f3f40267dc922f0fda287484435e1fd8709bade3e87c3829e2f945bb5e4aa 249a71cc6822d6bdd5bb9e727aac81c6549693b418e9c0987b96850ee332c940
-R 6fb3b1c5ffde39ec234334a7c5ffcb56
+P 13c4c9088cc8a2426e30a2ad1e9b9969407249281c6ed16653d43a0e6852a2e4
+R c79f76fc898939a9f2cc931eb9a2c482
 U drh
-Z 90ae5651a54d924d6159985985e1584c
+Z e1fe560394403461c8187fdaaf345432
diff --git a/manifest.uuid b/manifest.uuid
index 88f1bf8bca..13001fa395 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-13c4c9088cc8a2426e30a2ad1e9b9969407249281c6ed16653d43a0e6852a2e4
\ No newline at end of file
+dcb7772d7695ddbc0fe89e06c07ff4a6ae4fa05de914e2ec10b5cc07a62ed49f
\ No newline at end of file
diff --git a/src/whereexpr.c b/src/whereexpr.c
index e5e566bbfe..e360001931 100644
--- a/src/whereexpr.c
+++ b/src/whereexpr.c
@@ -1385,6 +1385,14 @@ static void exprAnalyze(
   }
 #endif /* SQLITE_OMIT_OR_OPTIMIZATION */
 
+  else if( pExpr->op==TK_EXISTS ){
+    /* Perhaps treat an EXISTS operator as an IN operator */
+    if( (pExpr->flags & EP_VarSelect)!=0 ){
+      exprAnalyzeExists(pSrc, pWC, idxTerm);
+    }
+  }
+
+
 #ifndef SQLITE_OMIT_LIKE_OPTIMIZATION
   /* Add constraints to reduce the search space on a LIKE or GLOB
   ** operator.
@@ -1611,10 +1619,6 @@ static void exprAnalyze(
   }
 #endif /* SQLITE_ENABLE_STAT4 */
 
-  if( pExpr->op==TK_EXISTS && (pExpr->flags & EP_VarSelect) ){
-    exprAnalyzeExists(pSrc, pWC, idxTerm);
-  }
-
   /* Prevent ON clause terms of a LEFT JOIN from being used to drive
   ** an index for tables to the left of the join.
   */